Ejector-Enhanced Heat Recovery Refrigeration System

ABSTRACT

A refrigerated transport system comprises: an engine. A vapor compression system comprises: a compressor for compressing a flow of a refrigerant; a first heat exchanger along a refrigerant flowpath of the refrigerant; and a second heat exchanger along the refrigerant flowpath of the refrigerant. A heat recovery system has: a first heat exchanger for transferring heat from the engine to a heat recovery fluid along a heat recovery flowpath; and a second heat exchanger along the heat recovery flowpath. The heat recovery system second heat exchanger and the vapor compression system first heat exchanger are respective portions of a shared tube/fin package.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of U.S. patent application Ser. No. 16/094,345,filed Oct. 17, 2018, entitled “Ejector-Enhanced Heat RecoveryRefrigeration System”, which is a 371 US national stage application ofPCT/US17/29326, filed Apr. 25, 2017, which claims benefit of U.S. PatentApplication No. 62/331,313, filed May 3, 2016, and entitled“Ejector-Enhanced Heat Recovery Refrigeration System, the disclosure ofwhich applications are incorporated by reference herein in theirentireties as if set forth at length.

BACKGROUND OF THE INVENTION

The invention relates to refrigeration. More particularly, the inventionrelates to heat recovery refrigeration systems such as refrigeratedtransport systems.

A transport refrigeration system used to control an enclosed area, suchas the box of a truck, trailer, intermodal container, or the like,functions by absorbing heat from the enclosed area and releasing heatoutside of the box into the environment. A number of transportrefrigeration units, including units currently sold by assignee, employa reciprocating compressor to pressurize refrigerant to enable theremoval of heat from the box.

A number of systems power the vapor compression system via an internalcombustion engine. Some systems directly couple the engine to thecompressor to mechanically drive the compressor. Others electricallypower the compressor via a generator. When an engine is present, anumber of systems have been proposed to use heat recovery from theengine. Several recent systems include those of US Patent ApplicationPublication No. 2012/0116594A1 of Aidoun et al., published May 10, 2012.

SUMMARY OF THE INVENTION

One aspect of the invention involves a refrigerated transport systemcomprising an engine. A vapor compression system comprises: a compressorfor compressing a flow of a refrigerant; a first heat exchanger along arefrigerant flowpath of the refrigerant; and a second heat exchangeralong the refrigerant flowpath of the refrigerant. A heat recoverysystem has:

a first heat exchanger for transferring heat from the engine to a heatrecovery fluid along a heat recovery flowpath; and a second heatexchanger along the heat recovery flowpath. The heat recovery systemsecond heat exchanger and the vapor compression system first heatexchanger are respective portions of a shared tube/fin package.

In one or more embodiments of any of the foregoing embodiments, aseparate subcooler has respective legs along the vapor compressionflowpath and the heat recovery flowpath and the heat recovery systemsecond heat exchanger is a condenser.

In one or more embodiments of any of the foregoing embodiments, there isno separate subcooler; and the heat recovery system second heatexchanger is an evaporator.

In one or more embodiments of any of the foregoing embodiments, the heatrecovery system further comprises: an ejector having a motive flowinlet, a secondary flow inlet, and an outlet; a pump; and a loop of theheat recovery flowpath passing through the pump to the heat recoverysystem first heat exchanger, through the motive flow inlet and from theoutlet back to the pump.

In one or more embodiments of any of the foregoing embodiments, the heatrecovery system first heat exchanger has a leg along a coolant flowpathof the engine.

In one or more embodiments of any of the foregoing embodiments, therefrigerated transport system further comprises: an engine radiator; anda valve along the coolant flowpath for apportioning a total coolant flowbetween the radiator and the heat recovery system first heat exchanger.

In one or more embodiments of any of the foregoing embodiments, theengine is coupled to the compressor to drive the compressor.

In one or more embodiments of any of the foregoing embodiments, theengine is coupled to the compressor to mechanically drive thecompressor.

In one or more embodiments of any of the foregoing embodiments, theengine is mechanically coupled to an electrical generator and theelectrical generator is electrically coupled to an electric motor of thecompressor.

In one or more embodiments of any of the foregoing embodiments, therefrigerated transport system further comprises a refrigeratedcompartment in thermal communication with the vapor compression systemsecond heat exchanger.

In one or more embodiments of any of the foregoing embodiments, therefrigerated transport is a truck or a trailer.

In one or more embodiments of any of the foregoing embodiments, theengine, vapor compression system, and heat recovery system are mountedalong a front of the compartment.

In one or more embodiments of any of the foregoing embodiments, thevapor compression system refrigerant and the heat recovery fluid aredifferent from each other.

In one or more embodiments of any of the foregoing embodiments, therefrigerant is less flammable, less toxic, and/or less harmful to thecontents of the refrigerated compartment than the heat recovery fluid.

In one or more embodiments of any of the foregoing embodiments, a methodfor operating the refrigerated transport system comprises, in a firstmode: running the engine to drive the compressor to compress the flow ofrefrigerant and drive the refrigerant along the refrigerant flowpath;transferring the heat from the engine to the heat recovery fluid alongthe heat recovery flowpath; and rejecting heat from the refrigerant inthe vapor compression system first heat exchanger.

In one or more embodiments of any of the foregoing embodiments, heat isabsorbed by the heat recovery fluid in the heat recovery system secondheat exchanger.

In one or more embodiments of any of the foregoing embodiments, in thefirst mode heat is rejected by the heat recovery fluid in the heatrecovery system second heat exchanger.

In one or more embodiments of any of the foregoing embodiments, aseparate subcooler has respective legs along the vapor compressionflowpath and the heat recovery flowpath. The method further comprises,in the first mode transferring heat from the refrigerant in the vaporcompression system t to the heat recovery fluid in the heat recoverysystem in the subcooler via a refrigerant-refrigerant heat exchangewithout airflow.

In one or more embodiments of any of the foregoing embodiments, therefrigerated transport system further comprises a radiator and themethod further comprises, in the first mode using a valve to apportionengine coolant between the heat recovery system first heat exchanger andthe radiator.

Another aspect of the invention involves a combined cooling heating andpower (CCHP) system comprising: a heat source. A vapor compressionsystem comprises: a compressor for compressing a flow of a refrigerant;a first heat exchanger along a refrigerant flowpath of the refrigerant;and a second heat exchanger along the refrigerant flowpath of therefrigerant. A heat recovery system has: a first heat exchanger fortransferring heat from the heat source to a heat recovery fluid along aheat recovery flowpath; and a second heat exchanger along the heatrecovery flowpath. The heat recovery system second heat exchanger andthe vapor compression system first heat exchanger are respectiveportions of a shared heat exchanger for rejecting heat to a heattransfer fluid. Further embodiments may variations be along the lines ofthe other embodiments discussed above and below.

In one or more embodiments of any of the foregoing embodiments, the heatsource comprises an engine and an electric generator is mechanicallycoupled to the engine to be driven by the engine.

In one or more embodiments of any of the foregoing embodiments, theshared heat exchanger is a water-cooled condenser (WCC).

In one or more embodiments of any of the foregoing embodiments, thewater-cooled condenser is selected from the group consisting of: a shelland tube WCC; tube-in-tube water WCC; and a brazed plate WCC.

Another aspect of the invention involves a system comprising a heatsource. A vapor compression system comprises: a compressor forcompressing a flow of a refrigerant; a first heat exchanger along arefrigerant flowpath of the refrigerant; and a second heat exchangeralong the refrigerant flowpath of the refrigerant. A heat recoverysystem has: a first heat exchanger for transferring heat from the heatsource to a heat recovery fluid along a heat recovery flowpath; and asecond heat exchanger along the heat recovery flowpath. The heatrecovery system second heat exchanger and the vapor compression systemfirst heat exchanger are respective portions of a shared heat exchangerfor rejecting heat to a heat transfer fluid and/or are in common (e.g.,series or parallel) along a heat transfer fluid flowpath. Furtherembodiments may variations be along the lines of the other embodimentsdiscussed above and below.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a refrigeration system of a refrigeratedtransport system.

FIG. 2 is a schematic view of the refrigerated transport system.

FIG. 3 is a schematic view of a second refrigeration system.

FIG. 4 is a schematic view of a third refrigeration system.

FIG. 5 is a schematic view of a fourth refrigeration system.

FIG. 6 is a schematic view of a combined cooling heating and power(CCHP) system.

FIG. 6A is a view of a shell and tube condenser of the CCHP system ofFIG. 6.

FIG. 7 is a schematic view of a second CCHP system.

Like reference numbers and designations in the various drawings indicatelike elements.

DETAILED DESCRIPTION

FIG. 2 shows a refrigerated transport unit (system) 20 in the form of arefrigerated trailer. The trailer may be pulled by a tractor 22. Theexemplary trailer includes a container/box 24 defining aninterior/compartment 26. An equipment housing 28 mounted to a front ofthe box 24 may contain an electric generator system including an engine30 (e.g., diesel) and an electric generator 32 mechanically coupled tothe engine to be driven thereby. A refrigeration system 34 may beelectrically coupled to the generator 32 to receive electrical power.

FIG. 1 shows further details of the exemplary refrigeration system 34.The system 34 includes a control system 200. The control system 200 mayinclude: one or more user interface (e.g., input/output) devices 202;processors 204; memory 206; storage 208; and hardware interface devices210 (e.g., ports).

The system 34 further includes a compressor 40 having a suction (inlet)port 42 and a discharge (outlet) port 44. An exemplary compressor 40 isan electrically-powered reciprocating compressor having an integralelectric motor 46. The compressor 40 may be coupled to the controlsystem 200 to regulate its operation and to the generator 32 via powerlines 48 to receive power. The compressor is a portion of a vaporcompression system 50 having a recirculating refrigerant flowpath orloop 52. The exemplary refrigeration system 34 further comprises a heatrecovery system 56 having a heat recovery flowpath or loop 58.

Along the refrigerant flowpath 52, the vapor compression system 50includes, in a downstream direction from the discharge port or outlet44, a heat exchanger 60, a leg 62-1 of a subcooler 62, an expansiondevice 64, and a heat exchanger 66 before returning to the suction port42. In a normal operational mode, the heat exchanger 60 is a heatrejection heat exchanger (condenser or gas cooler) and the heatexchanger 66 is a heat absorption heat exchanger (evaporator). Both heatexchangers 60 and 66 may be refrigerant-air heat exchangers havingrespective fans 70 and 72 driving airflows 520 and 522 along airflowpaths across the heat exchangers. The heat exchanger 66 is inthermal communication with the box interior to cool the box in thenormal cooling mode(s). The heat exchanger 60 is in thermalcommunication with an exterior of the box to reject heat to the airflow520 in the normal cooling mode. Thus, the airflow 520 may be an externalairflow and the airflow 522 may be an interior airflow.

As is discussed further below, the subcooler 62 is arefrigerant-refrigerant heat exchanger wherein the leg 62-1 along therefrigerant flowpath 52 is in heat exchanger relation with a leg 62-2along the heat recovery flowpath 58. The heat recovery fluid flowingalong the heat recovery flowpath may go through a phase change (e.g., asdiscussed below) and may otherwise be characterized as a refrigerant.However, for convenience of reference, it will be hereafter referred toas the heat recovery fluid. The heat recovery fluid and the refrigerantmay, in some implementations, have identical compositions or may bedifferent. In the latter situation, there will be no fluid communicationbetween the two loops. In the former, there could be.

The heat recovery system 56 includes a pump 80 having an inlet 82 and anoutlet 84. The pump is along a sub-loop or flowpath branch 86 of theheat recovery flowpath 58 which also includes the primary flowpath of anejector 90. The branch 86 may also provide a convenient location for areceiver (not shown; e.g., at the pump inlet). The ejector has a primaryor motive flow inlet 92 at the inlet of a nozzle (e.g., aconvergent-divergent nozzle) 94 and an outlet 96 at the downstream endof a diffuser 98. The ejector further comprises a mixer 100 and asecondary or suction inlet port 102. Sequentially along the loop 86proceeding downstream from the pump 80 in a normal operational mode,flow passes through a leg 110-1 of a heat exchanger 110, the ejectorprimary inlet 92, the ejector outlet 96, and a heat exchanger 112 beforereturning to the pump.

A second sub-loop or flowpath branch 120 branches off from the loop 86between the heat exchanger 112 and pump 80 and passes sequentiallythrough an expansion device 122, the heat recovery loop leg 62-2 of thesubcooler 62, and returns to the ejector secondary or suction port 102.In normal heat recovery operation, the heat exchanger 110 is a generatorheat exchanger transferring heat from the engine to the heat recoveryloop. Similarly, the heat exchanger 112 is a heat rejection heatexchanger. The heat recovery loop leg 62-2 of the subcooler serves as anevaporator or heat absorption heat exchanger absorbing heat from thevapor compression system leg 62-1 of the subcooler.

FIG. 1 further shows, associated with the engine 30, a radiator 130 anda fan 132 (electric or mechanical) driving an airflow 524 across theradiator. For engine cooling, a coolant pump 134 (e.g., mechanical orelectric) may drive fluid along a recirculating loop 136 outputtingheated coolant from the engine and returning reduced temperaturecoolant. The coolant may be a conventional engine coolant such as awater and glycol mixture. In the exemplary implementation, a valve 140allows selective communication of the coolant flow to the heat exchanger110 and/or the radiator 130. In this example, the valve 140 is aproportioning valve allowing a stepwise or continuous allocation of therefrigerant flow between the heat exchanger 110 and the radiator 130. Inalternative embodiments, the valve is bi-static. For example, oneconfiguration of a bi-static valve may alternatively deliver coolant tothe heat exchanger 110 or radiator while not delivering to the other.Yet other bi-static situations involve having flow to both in at leastone condition.

In the exemplary implementation, the heat exchangers 60 and 112 are partof a single heat exchanger unit. In an exemplary implementation, theunit is a single bank of tubes and fins with the heat exchangers 60 and112 representing separate groups of legs of the tubes but sharing finsand tube plates. In the exemplary illustrated implementation, the twoheat exchangers 60 and 112 are in series along an air flowpath for theairflow 520. In the exemplary embodiment in the normal cooling mode, theheat exchanger 112 is downstream of the heat exchanger 60 along theassociated air flowpath. The integrated heat exchanger with seriesairflow may have advantages in terms of economizing on space,economizing on heat exchanger cost, and economizing on fan cost (e.g.,by having a single fan servicing both). By having the heat exchanger 60upstream along the air flowpath, it receives the coldest air in normaloperation.

A number of variations are possible. Plural of these variations maycoexist. One group of variations involves having the compressor 40mechanically powered by the engine 30 (e.g., directly driven or drivenvia a transmission) rather than electrically driven. This wouldeliminate the motor 46 and eliminate the generator 32 (although theengine may include a generator for powering the engine (e.g., providingspark, starting, and the like)).

In other variations, the valve 140 may be eliminated so that all coolantpasses in series through the heat exchanger 110 and the radiator 130(e.g., FIG. 3).

Other variations involve eliminating the radiator 130 (and its fan 132)so that the coolant supply and return pass directly between the engineand the heat exchanger 110. The radiator elimination may reduce cost andspace consumed. The heat recovery loop takes heat from the enginecoolant and the subcooler 62 and rejects it to air at the heat exchanger112. In order to protect the engine, the operation of this variationcould be prioritized for engine heat rejection. For example this mayinvolve running with the vapor compression system in a less-efficientstate so as to consume more power (and thus require the engine toconsume more fuel) than if the engine were rejecting heat via theomitted radiator.

Other variations involve altering the cycles of the vapor compressionsystem 50 and/or the heat recovery system 56. The exemplary illustratedsystems are relatively simple and many additional features could beadded as are known in the art or yet developed. These, for example,include the use of economized vapor compression systems or ejectorcycles in the vapor compression system.

Further variations involve using engine exhaust heat in addition to oras an alternative to engine coolant for transferring heat to the heatrecovery system in the heat exchanger 110. These variations can increasethe amount of heat and the temperature at heat exchanger 110, leading toincreased capacity and efficiency of the heat recovery loop.

Yet further variations involve adding a feature such as a de-superheaterlinking the two loops in addition to the subcooler 62. An exemplaryde-superheater is a refrigerant-refrigerant heat exchanger having a legalong the vapor compression system upstream of the heat exchanger 60 anda leg along the heat recovery flowpath downstream of the subcooler. Thismay decrease the compressor work and increase the system efficiency.

Yet further variations involve placing the heat exchangers 60 and 112 inparallel (e.g., FIG. 4) along air flowpaths rather than in series whilestill maintaining them as part of a single unit. In general, parallelflow increases thermodynamic efficiency because both heat exchangers areexposed to ambient inlet air (rather than one being exposed to airheated in the other). However, this may require increased space andpotentially cost. In one group of examples, a single fan may pass flowacross both in parallel, thus eliminating a fan and its cost. In otherimplementations, there may be separate fans 70-1, 70-2, which couldprovide better control separate flows 520-1, 520-2.

Yet further variations involve effectively eliminating the subcooler 62and replacing it with an evaporator 63 in the heat recovery system(e.g., FIG. 5). The evaporator (heat rejection heat exchanger) may beplaced in series with the heat exchanger 60 instead of placing the heatrejection heat exchanger 112 in series. In such implementations, theevaporator and the heat exchanger 60 may be the two sections of theintegrated single unit. This would involve adding one net fan over theFIG. 1 embodiment with one fan 70-2 driving airflow 520-2 only acrossthe heat exchanger 112 and another fan 70-1 driving airflow 520-1 inseries across the added heat recovery system evaporator and the heatexchanger 60. An exemplary airflow direction places the added evaporatorupstream to precool the air (which then flows across the heat exchanger60) and thereby effectively provide interloop heat transfer from thevapor compression system to the heat recovery system.

Other possible integrations involve yet further integrating heatexchangers and/or combining air flowpaths. One example modifies the FIG.5 configuration by eliminating the fan 70-2 and integrating the heatexchanger 112 with heat exchangers 60 and 63 as sections of theintegrated single unit (e.g., 112 could be immediately downstream of 60along the flowpath 520-1 of FIG. 5).

Further variations may involve stationary or fixed site installations.FIG. 6 shows an exemplary fixed site installation or system 320 embodiedas a combined cooling, heating, and power (CCHP) system. Generally, likecomponents to the system 20 are shown with like numerals even though thescale or form may ultimately be different in any particularimplementation. The CCHP system 320 features refrigerant-water(generically including other liquids such as brine, glycols, othersolutions, and the like)) heat exchangers in place of refrigerant-airheat exchangers. In addition to powering the compressor motor 46, thegenerator 32 powers additional electric loads 322 of a building (e.g.,beyond the loads of the system itself and, more broadly beyond heatingventilation and air conditioning (HVAC) loads). The vapor compressionsystem evaporator 366 (legs 366-1 and 366-2 in heat exchange relation)cools a water flow 572 along a water flowpath (e.g., including along leg366-2 and pumped via a pump 372 along a water line/conduit to/fromcooling loads 371 such as air handling units, building cold water andthe like). Condenser sections 360 and 412 along the two loops may berespective sections of a single refrigerant-water heater exchanger 600(FIG. 6A). One example is a shell and tube heat exchanger. Anotherexample is a brazed plate heat exchanger. Yet another example is atube-in-tube heat exchanger. FIG. 6 shows a water flow 570 along a waterflowpath (e.g., pumped via a pump 369 along a water line/conduit)from/to a cooling tower 650 through the unit 600. The unit 600 has awater inlet 602 and a water outlet 604. The exemplary unit 600 is ashell and tube heat exchanger having a shell with a cylindrical wall 610and end caps 612 and 614. Plates 616 and 618 define plena at respectiveend and are spanned by tube groups 620 and 622. The first end plenumformed by the plate 616 and end cap 612 is subdivided by a plate 624into respective inlet and outlet plena 630 and 632. The second endplenum 634 defines a turn in the flowpath with the flowpath proceedingsequentially through the inlet 602 into the plenum 630, through thetubes 620 to the plenum 634, and then back through the tubes 622 to theplenum 632 and the outlet 604.

To cool the fluid of the two loops, the interior of the shell is furthersubdivided by a dividing plate 640 into chamber 642 and 644 whicheffectively form the condensers 360 and 412, respectively. The chamber642 has an inlet 646 and an outlet 648. The chamber 644 has inlet 647and an outlet 649. Refrigerant from the compressor passes into the inlet646 where it rejects heat to the sections of the tubes 622 and 620within the chamber 642 before passing out the outlet 648 to go to thesubcooler. Similarly, heat recovery fluid from the ejector passesthrough the inlet 647 and rejects heat to the water flowing in sectionsof the tubes 622 and 620 within the chamber 644 before exiting theoutlet 649.

In yet further variations, instead of being an engine, the heat source30 may be a fuel cell.

Other variations may be along the lines noted above for the refrigeratedtransport system. For example, FIG. 7 shows a CCHP system 720 whereinthe refrigerant-refrigerant subcooler is replaced with arefrigerant-water precooler 710 having a leg 710-2 along the coolingwater flowpath rejecting heat to a leg 710-1 (acting as an evaporator)along the flowpath 58 upstream of the ejector suction port. This furthercools the cooling water from the tower to further cool the refrigerantand heat recovery fluid in the unit 600 (in a fashion similar to theunillustrated modification of FIG. 5 integrating the condenser 112 intothe unit with 60 and 63).

In a variation on the FIG. 7 system, rather than having a singleintegrated unit 600, there are physically separate WCC for the twoloops, each with its own water supply and return from the tower. Theprecooler (leg 710-1 forming heat recovery loop evaporator) cools thewater supply (along leg 710-2) for the vapor compression system's WCC.Thus, the precooler (leg 710-2) and the vapor compression system's WCCare in series along the heat transfer fluid flowpath (the cooling waterflowpath for the vapor compression system's WCC).

Thus, it is seen that one or more of several further shared features mayexist between the loops of the various systems. A first area involvesthe physical integration of the heat exchangers of the vapor compressionloop and heat recovery loop. Another area which may exist simultaneouslywith or alternatively to the first is the shared heat transfer fluid(air or water (generically including other liquids such as brine,glycols, other solutions, and the like)) whether in series or otherwise(e.g., the split series configuration of FIG. 6).

Yet further variations on the foregoing systems involve the particularworking fluids of the vapor compression system and heat recovery system.As mentioned above, they may be the same or different. In one possiblearea of differences, the refrigerant of the vapor compression system maybe relatively non-flammable (and/or less toxic, and/or less harmful tothe contents of the refrigerated compartment) when compared to the heatrecovery fluid. For example, appropriate isolation allows only potentialexposure/venting of the refrigerant into the box interior. The heatrecovery fluid may be isolated from the box so as to not be able toaccumulate in an enclosed space if there is a leak. Thus, one exemplarycombination is a carbon dioxide-based refrigerant (e.g., R744) and ahydrocarbon heat transfer fluid (e.g., R290). An alternative pair isR452A/R245fa.

The physical configuration of the system is merely illustrative and mayschematically represent any of a number of existing or yet-developedconstructions. The inventive methods described below may also beapplicable to other constructions.

The system may include various additional components including,receivers, filters, dryers, valves, sensors, and the like.

One or more embodiments of the present invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention. Forexample, when applied in the reengineering of baseline systemconfiguration or the remanufacturing of a baseline system, details ofthe baseline may influence or dictate details of the particularimplementation. Accordingly, other embodiments are within the scope ofthe following claims.

What is claimed is:
 1. A refrigerated transport system comprising: anengine; a vapor compression system comprising: a compressor forcompressing a flow of a refrigerant; a first heat exchanger along arefrigerant flowpath of the refrigerant; and a second heat exchangeralong the refrigerant flowpath of the refrigerant; and a heat recoverysystem having: a first heat exchanger for transferring heat from theengine to a heat recovery fluid along a heat recovery flowpath; and asecond heat exchanger along the heat recovery flowpath wherein: the heatrecovery system second heat exchanger and the vapor compression systemfirst heat exchanger are respective portions of a shared tube/finpackage.
 2. The refrigerated transport system of claim 1, wherein: aseparate subcooler has respective legs along the vapor compressionflowpath and the heat recovery flowpath; and the heat recovery systemsecond heat exchanger is a condenser.
 3. The refrigerated transportsystem of claim 1, wherein: there is no separate subcooler; and the heatrecovery system second heat exchanger is an evaporator.
 4. Therefrigerated transport system of claim 1, wherein the heat recoverysystem further comprises: an ejector having a motive flow inlet, asecondary flow inlet, and an outlet; a pump; and a loop of the heatrecovery flowpath passing through the pump to the heat recovery systemfirst heat exchanger, through the motive flow inlet and from the outletback to the pump.
 5. The refrigerated transport system of claim 1,wherein: the heat recovery system first heat exchanger has a leg along acoolant flowpath of the engine.
 6. The refrigerated transport system ofclaim 5, further comprising: an engine radiator; and a valve along thecoolant flowpath for apportioning a total coolant flow between theradiator and the heat recovery system first heat exchanger.
 7. Therefrigerated transport system of claim 1, wherein the engine is coupledto the compressor to drive the compressor.
 8. The refrigerated transportsystem of claim 7, wherein the engine is coupled to the compressor tomechanically drive the compressor.
 9. The refrigerated transport systemof claim 7, wherein the engine is mechanically coupled to an electricalgenerator and the electrical generator is electrically coupled to anelectric motor of the compressor.
 10. The refrigerated transport systemof claim 1, further comprising: a refrigerated compartment in thermalcommunication with the vapor compression system second heat exchanger.11. The refrigerated transport system of claim 10, being a truck or atrailer.
 12. The refrigerated transport system of claim 10, wherein theengine, vapor compression system, and heat recovery system are mountedalong a front of the compartment.
 13. The refrigerated transport systemof claim 1, wherein: the refrigerant and the heat recovery fluid aredifferent from each other.
 14. The refrigerated transport system ofclaim 13, wherein the refrigerant is less flammable, less toxic, and/orless harmful to the contents of the refrigerated compartment than theheat recovery fluid.
 15. A method for operating the refrigeratedtransport system of claim 1, the method comprising, in a first mode:running the engine to drive the compressor to compress the flow ofrefrigerant and drive the refrigerant along the refrigerant flowpath;transferring the heat from the engine to the heat recovery fluid alongthe heat recovery flowpath; and rejecting heat from the refrigerant inthe vapor compression system first heat exchanger.
 16. The method ofclaim 15, wherein, in the first mode: heat is absorbed by the heatrecovery fluid in the heat recovery system second heat exchanger. 17.The method of claim 15, wherein, in the first mode: heat is rejected bythe heat recovery fluid in the heat recovery system second heatexchanger.
 18. The method of claim 15, wherein: a separate subcooler hasrespective legs along the vapor compression flowpath and the heatrecovery flowpath; and the method further comprising, in the first mode:transferring heat from the refrigerant in the vapor compression system tto the heat recovery fluid in the heat recovery system in the subcoolervia a refrigerant-refrigerant heat exchange without airflow.
 19. Themethod of claim 15, wherein the refrigerated transport system furthercomprises a radiator and the method further comprises, in the firstmode: using a valve to apportion engine coolant between the heatrecovery system first heat exchanger and the radiator.
 20. A systemcomprising: a heat source; a vapor compression system comprising: acompressor for compressing a flow of a refrigerant; a first heatexchanger along a refrigerant flowpath of the refrigerant; and a secondheat exchanger along the refrigerant flowpath of the refrigerant; and aheat recovery system having: a first heat exchanger for transferringheat from the heat source to a heat recovery fluid along a heat recoveryflowpath; and a second heat exchanger along the heat recovery flowpath,wherein: the heat recovery system second heat exchanger and the vaporcompression system first heat exchanger are respective portions of ashared heat exchanger for rejecting heat to a heat transfer fluid and/orare in common along a heat transfer fluid flowpath.